1. Field of the Invention
The invention relates to a harvesting machine for harvesting corn and similar crops on stalks, wherein the harvesting machine has at least one circulating endless conveyor for engaging the crop which conveyor forms a crop feed area directing the crop toward an inlet opening of a processing device for further processing the crop, in particular, a chopper, wherein the endless conveyor has a lower cutting plane for the crop which is comprised of outwardly extending conveying and guiding elements as well as at least one cutting blade arranged below the conveying and guiding elements.
2. Description of the Related Art
From DE 33 24 899 C2 a harvesting machine is known in which, for separating the stalks of the crop, tools are provided which are nested in a link chain. The link chain is moreover provided with nested holding means for conveying the separated stalks. The stalks are fed to the inlet opening of a chopper or the like. For this purpose, between oppositely driven endless chains a feed area is provided in which also a deflection of the chains is carried out. In the area of this deflection the received stalks are fed also into the processing device so that a significant crop waste will result in this area. Accordingly, there is the risk that the crop is not completely guided through the chopper or the like but instead builds up in front of the inlet opening. Moreover, during the entire circulation of the conveyor crop material, in particular, the leaves or similar long-fiber components, will stick to the drivers of the chain so that there is the risk that the transport function of the drivers over the course of employment of the harvesting machine will decline.
Moreover, a harvesting machine of the aforementioned kind is known in which in the cutting plane conveying and guiding elements, for example, in the form of hook-shaped blades, of the endless conveyor are provided which interact with a cutting blade. This cutting blade can be mounted fixedly on the frame part of the harvesting machine. As an alternative, it is also possible to employ instead of the stationary blade rotating cutting disks or oscillatingly driven blades which interact either by a free cut or in interaction with the blades of the conveying and guiding elements of the endless conveyor. The cutting blade is provided with a continuous cutting edge so that each holding or cutting element has a corresponding blade area correlated therewith. During operation, such a configuration of the cutting action of the crop, e.g., a stalk of corn, can result in the cut being carried out always at the same location of the blade areas of the cutting blade so that at these locations increased wear results. Also, in these areas increased soiling occurs.
It is an object of the present invention to further develop a harvesting machine of the aforementioned kind such that increased wear on the cutting blades is counteracted. Moreover, the harvesting machine should have improved cleaning properties.
In accordance with the present invention, this is achieved in that the cutting blade has a stepped configuration with steps and, viewed in the running direction of the conveying and guiding elements, has cutting segments having cutting edges and extending at a slant outwardly relative to a circulating path of the conveying and guiding elements, wherein between two neighboring cutting segments a cutting segment step is formed.
The important advantage of the harvesting machine according to the present invention is that the service life of the cutting blade is significantly increased because of the step-shaped configuration of the cutting blade with steps. This also holds true for the conveying and guiding elements of the endless conveyor interacting with the cutting blade. As a result of the step-shaped cutting segments, i.e., a sequence of individual cutting segments with cutting edge areas extending at a slant outwardly relative in the running direction of the conveyor, the crop can be cut across the entire length of the respective cutting edge or across the length of the edge of the conveying and guiding element of the endless conveyor interacting with this cutting edge. In contrast to conventional harvesting machines with a continuous cutting edge of the cutting blade, the cutting action of, for example, the stalk, is not always carried out at the same location so that great wear at this location can be prevented. Moreover, the harvesting machine according to the invention has significantly improved cleaning properties in the area of the cutting plane which is, in particular, the result of the lower ends of the crop remains which are jammed between the conveying and guiding elements and the cutting blade being released upon passing the cutting segment step of the cutting blade segment and either are cut off or will drop.
It was found that the cutting output and also the desired improved cleaning action can be optimized, in particular, when the angle xcex2 of the cutting blade of a cutting segments relative to a baseline or reference line, which intersects the longitudinal axis of the travel direction of the harvesting machine at a right angle and/or is oriented tangentially to the circulating path of the endless conveyor, is smaller than the angle a of the slantedly extending area of the conveying and guiding elements. The angle xcex2 is preferably approximately xc2xdxcex1.
In conventional harvesting machines, the division T, i.e., the spacing of the coupling points of two neighboring conveying and guiding elements of the endless conveyor, is such that an end of the conveying and guiding elements formed as a counter blade is provided for each division T. This corresponds to a matching division. Preferably, a harvesting machine according to the invention is configured such that the number of counter blades is selected such that over the length of two divisions T of the conveying and guiding elements of the endless conveyor at least three ends of the conveying and guiding elements formed as counter blades are provided; this means that for two divisions T of the conveying and guiding elements at least three areas for receiving stalk-like crop material are provided. In this way, a reliable cutting action of the crop at higher driving speeds is also possible.
The step-shaped configuration of the cutting segments of the cutting blade is such that the cutting segment has a forward slant in the travel direction of the conveying and guiding elements across the entire width of the cutting segment and then has a sudden or abrupt drop, i.e., parallel to the longitudinal axis of the travel direction, to the initial dimension of the cutting blade of the preceding cutting segment. In this way, the desired release of the crop is possible once it has passed a cutting segment. The cutting edge can be provided with or without cylindrical grinding.
Each cutting segment can be an individual blade mounted, for example, on the harvesting machine frame. However, it is also possible to provide one blade with two cutting segments or more.